Electric alarm



(No Model.)

W S HULL ELEGTRIO ALARM.

No. 545,653. Patented Sept. 3, 1895.

UNITED STATES PATENT OFFICE.

wrLLIAM s. HULL, oF DALLAs, TEXAs.

ELECTRIC ALARM.

SPECIFICA'I'ION formng part of Letters Iatent No. 545,653, dated September 3, 1895. Application filed November 26, 1894- Serial No. 529,951. (No model.)

To aZZ whom zl may conccrn:

Be it known that I, WILLIAM S. HULL, a citizen of the United States, residing at Dallas, in the county of Dallas,,State of Texas, have invented certain new and useful improvements in Electric Alarms, of which the following is a specification, reference being had therein to the accompanying drawings.

This invention relates to certain new and useful improvements in electric alarms designed for use in connection with any and all forms of systems of safe and vault protection, and it has for its objects, among others, to provide a simple, yet efficient, device for this purpose, in which is employed but a single magnet, so arranged as to produce as good, if not a better, result as any instrument with two coils. The armaturev of this magnet is suspended between the two contact points, the magnet pulling the armature in one direction and a spring exerting its influence in the opposite direction, the adjustment of the spring equalizing the pull of the magnet. The armature has a pivoted horizontal arm, which is supported at one end upon a platina point attached to a post having provisions for its adj ustment, and the said arm arranged to slide back and forth under conditions which will be hereinafter set forth. The friction caused by this sliding of the arm or bar assists in maintaining the suspension of the armature between the contact points. Means are provided for increasing or diminishing this friction, and the arm is provided with a platina point and an insulator so arranged that normally the platina, point on the post will engage the said insulator; but as the sliding arm moves either one way or the other the insulator moves off of the platina point `and the arm drops and its platina point comes in contact with that on the post. The lengthening of the line moves the slidin g arm in one direction and sounds an alarm, and the arm is moved in the opposite direction with a like result upon the shortening of the line from.

any cause. The alarm will be continuous, because the arm cannot move in either direction until it is lifted up and the insulator rests upon the platina point on the post.

Other objects and advantages of the invention will hereinafter appear and the novel features thereof will be specifically defined by the appended claims.

The invention is clearly illustrated in the accompanying drawings, which, with the letters of reference marked thereon, form a part of this specification, and in which- Figure 1 is a view partly in elevation and partly in section, illustrating my invention. Fig. 2 is a perspective detail of the contactpoints and a port-ion of the sliding arm of the armature.

Like letters of reference indicate like parts in both of the views.

Referring now to the details of thedrawings by letter, A designates a base or support to which are connected the binding-posts B and other parts of the apparatus.

Cis a post rising from the base, and through this post extends a horizontal bar D, to which is connected one end of a spring E, the other end of which is connected with the armature of the magnet, as shown in Pig. 1. Suitable means are provided for adjusting the arm to regulate the tension of the spring. In this instance such means consists simply of abinding-screw d and an adjusting-screw e.

F are uprights,upon and. between which is supported the magnet G, of any suitable form, and o'ne of these uprights is provided at its upper end with the horizontal portion f, which has a slot through which works the upper end of the armature. H, which is pivotally connected at its lower end with the base, as shown at h, the spring E being connected therewith at a point above its pivot, as shown.

The binding-posts shown at the right of Fig. 1 are those of the main line, the same being connected by the wires a with the magnet, as shown, while the wires b connect the bindingposts at the left, which are those of the alarmcircuit, with the armature and the upright F at the right of Fig. 1. To the upper end of the armature, which passes loosely through the slot f' in thev lateral portion of the upright, is pivotally connected at 'i the horizontal bar or arm I, one end of which is passed loosely through a slot g in the upper end of the upright F at the right of Fig. 1.

J is a post secured at its lower end to the right-hand side upright F, as at j, while at its upper end it carries a platina strip or point IOO j', the said post being` adjustableby means of a thumb-screw K, as shown in Fig. l. On the free end of the horizontal arm I of the armature is a platina strip L, secured thereto in any suitable manner, in this instance byan insulatng-band M, which embraces the arm as best shown at Fig. 2, the insulating band being extended beyond the platina strip, as shown, for a purpose which will soon be made apparent. The friction of the horizontal arm at the sliding point is increased or diminished by means of the weight or weghts N, slidingly mounted upon awire O, connected with the said horizontal arm, as shown.

VVith the parts constructed and arranged substantially as above specitied the operation will be as follows: The instrument being' properly adjusted With the armature in suspension, the platina pointj' of the post J rests upon the insulator M. Now the platina points are out of contact, and if the current on the Wire is increased-as,for instance in short-circuiting, cntting out a resistance-coil, or otherwise shortening the line-then the armature will move up to the magnet. The additional strength thus given to the magnet permits it to overcome the pull of the spring and the friction of the slide. The sliding arm is moved and the insulator is moved away from the platina point on the post and the sliding arm drops until its platina strip engages the platina point on the post and the alarm is sounded. If the Wire is lengthened or broken in two after the armature is adjusted in suspension, then the armature will move away from the magnet, the spring being more powerful than the currentv in the magnet and overcoming the friction of the slding arm, and the insulator is moved away from the platina point of the post and the arm drops with its platina strip in contact with that on the post and the alarm is soun'ded. The ring of the bell will be continuous, for the armature cannot move either way until the sliding bar or arm has been raised and the insulator rests upon the platina point of the post J.

Modifications in detail may be resorted to without departing from the spirit of the invention or sacrificing any of its advantages. For instance, the platina point can be placed on the slding arm and the insulator and platina strip upon the post, being a mere reversal of the arrangement above described.

Other similar changes Would be considered within the scope of the invention.

What is claimed as new is-- 1. In a device for the purpose specified, the combination of a magnet and its armature, a Vertical and a horizontally-disposed contact point, and a sliding bar or arm carrying one of said contact points and an insulator nori mally resting upon the Vertical contact point and adapted when moved in either drection to fall od of the Vertical contact and bring the Vertical contact and the conducting part of the sliding arm into contact, substantially as specified.

2. In a device for the purpose specified, the combination with a magnet, the pivoted armature and its pivoted portion, of a contact point, and a cooperating contact point and an insulator, in a different plane from and dividing said cooperating contact point, substantially as specified.

3. The combination with the magnet, the armature and the sliding arm thereon, of the contact point, the platina strip and the insu lator in a different plane, substantally as and for the purpose specified.

4. The combination with the magnet, the pivoted armature, the alarm connections and the main line, of the sliding arm carried by the armature, the contact points the nsulator dividing one of said points and the means for keeping them normally separated, said means being in a different plane from the contact on the arm, as set forth.

5. A magnet and a pivoted armature and sliding arm connected with said armature and provided with a contact point and an insnlator d'ividing the same and arranged upon a dilferent plane, combined with an adjustable pivotally-mounted Vertical contact arm. upon which the sliding arm normally rests as set forth.

In testimony Whereof I affix my signature in presence of two witnesses.

WILLIAM S. IIULL.

W'itnesses:

THOMAS J. COFFEY. II. O. BARLOW. 

